The present invention relates generally to a system and method of providing radiation treatment, and in one embodiment, specifically to a system and method for cone beam real time radiation treatment and optimization.
Various systems and methods exist to provide radiation therapy treatment of tumorous tissue with high-energy radiation. While some patient conditions require whole body radiation treatments, many forms of radiation treatment benefit from the ability to accurately control the amount, location and distribution of radiation within a patient's body. Such control often includes applying various levels of radiation to various areas of the tumorous region. For example, in some instances it is desirable to apply a greater dosage of radiation to the interior portion of a tumorous region than to the exterior portions of the region. As another example, in some instances it is desirable to minimize the dosage of radiation to non tumorous regions where radiation may have deleterious effects. Due to a variety of contributing factors, achieving accurate control of the amount, location and distribution of radiation within the patient's body can be difficult. Among these factors are movement in the patient's body, changes in organ or inter organ structure or composition, and changes in the relative position of a patient's organs.
Prior to a radiation therapy, the patient undergoes extensive imaging procedures to determine the exact size, shape and location of the tumorous region. The radiation therapy typically includes a plurality of radiation sessions over a period of several weeks. In a radiation session, the patient is subjected to radiation from an accelerator that emits a beam of radiation energy collimated and oriented to entry the patient's body from a particular angle. Varying the intensity and the entry angle of the incident radiation beam allows radiation specialist to generate a radiation dose volume that corresponds to the size, shape, and location of the tumorous region.
Several factors may prevent optimal radiation exposure to the tumorous region and minimal radiation exposure of the healthy tissue regions. For example, movement as minor as those attributable to the patient breathing may affect radiation dosages. Minor changes in patent's position from the imaging gantry to the treatment gantry may radically alter the position of the tumorous region or organ. The size, shape, or location of the tumor may change between the radiation treatment sessions. In addition, varying degrees of tissue density and radiation attenuation characteristics may have a dramatic effect upon the effectiveness and accuracy of a dosage prescription.
Accordingly, it would be advantageous to have an apparatus and a method for a radiation therapy, wherein the quality of which is not significantly affected by such factors as changes in patient anatomy, improper patient positioning and movement. It is desirable for the apparatus and the method to provide an accurate radiation dosage to the tumorous region in a patient and to minimize the radiation exposure of the healthy regions of the patient under the radiation therapy. It would be of further advantage for the apparatus and the method to be able to ensure consistently high quality of the radiation therapy.